The British invaded the Capitol yesterday in the largest force since they burned it down in 1814. Both sides claimed victory.

Sen. Charles Mathias (R-Md.) introduced about 20 members of Parliament -- lenders to the National Gallery of Art exhibition "Treasure Houses of Britain" -- on the floor of the House, interrupting a debate on a farm bill, while several of their wives looked down from the diplomatic guests gallery.

Said Lady Elliot of Harwood, one of the first women to make a speech in the House of Lords: "We were impressed. Parliament wouldn't stop for anyone." She went on to guess that almost "60 percent of the lenders are members of Parliament." The Duke of Rutland and the Earl of Bathurst agreed.

"Quite an honor. An historic occassion. Much more informal than Parliament. We'd never stop debate, even very dull debate, to welcome visitors," said the earl, who lives in Cirencester Park. He wore a family jewel -- a three-feathers diamond tie pin, the insignia of the Prince of Wales' own hussars, one of three bestowed to his ancestor for heroism in the Boer War. His wife, "because we're going on to tour the White House and meet Nancy Reagan," wore a matching, larger diamond feather pin.

Mathias, a history buff, gave a short tour of the Capitol, apologizing to his guests for mentioning in the Old Senate Chamber that "we had to build this room after the British burned the Capitol in 1814." Pointing to the canopy for the president of the Senate, he said, "At the dedication of the restoration, even Vice President Nelson Rockefeller looked mighty small under it."

Meanwhile, about 160 more lenders to the exhibition (including wives, sons-in-law, husbands, mothers and other supporters) toured the Capitol and then lunched (fish and Virginia ham followed by pumpkin tarts) with Mathias in the Mike Mansfield room. Just who paid for the lunch was not certain, since the Senate isn't allowed to pick up the tab. But apparently Mathias' office thought the National Gallery's credit was good.

On the red London-style double-decker going over, much of the conversation was about the houses and objects in the show. Lady Julie de Chair said that when she and her husband, Somerset de Chair, saw their large marble statuary group in the National Gallery, "we thought it was wonderful. We'd never paid much attention to it at home, except it always seemed too big for the low-ceilinged room." The couple lent objects from three of their houses.

The morning began with a seminar at the National Gallery on the care and feeding of historic houses. Lady Victoria Leatham of Burghley House told about finding a Renaissance jeweled horse in an orange box that hadn't been unpacked since 1690. "In a tin box behind the door of my husband's dressing room, we found three salmon flies on top of a group of my father's canceled checks, and underneath were letters from Henry III, Henry VIII and Queen Elizabeth I."

Elsie Gibbs of Sheldon Manor said she had to get up every morning at 5 a.m. to bake scones for their restaurant in the old stables. Her husband, she said, completely restored their estate by himself. Lord March of Goodwood House explained that his house was well suited for his multiple businesses because it is divided into three sections. "My ancestor intended five more, but he ran out of money and died." Anthony Mitchell, a national trust official who is one of nine families living in flats in Dyrham Park, said the difficulties in living in a historic house -- "including the floods that occur when the ball cock does not rotate properly" -- about balance out the advantages.